1. Field of the Invention
The present invention relates to an electric water heater having a filtering device, and particularly to an electric water heater which is able to avoid any scales from generating, by means of the combination of the porous magnetic resin film and the calcium sulfite filter membrane respectively for the absorption of metallic impurities in water and chlorine removal.
2. Description of Related Art
In a conventional electric water heater, after the cool water is added, a heating means such as an igniting device and hot water coil is used to heat the water for the user to use.
The regional nature of the hard water gives the formation of scales after heating. The accumulation of the scales adversely affects, even damage the electric water heater. One approach has been proposed to solve the above problem by using gas as the heating fuel. The gas water heater needs to be installed in a well-ventilated location. Therefore, it cannot be applied in the bathroom of a general suite or a confined environment. The gas water heater produces carbon monoxide poisoning, which is often heard in our society. Furthermore, when the gas exhausts, some inconveniences occur. For example, the gas is cut off when the user is taking shower.
For the currently available water heaters, no filters are designed exclusively for the electric water heater. Most of the commercially available filters contains active carbon and are used to filter the drinking water. They cannot be replaced directly. Even though they are replaced, there often happen problems such as unqualified specification and high cost.
Therefore, there is a need of a novel electric water heater which overcomes the above shortcomings in the prior art.